Which Power Tube/Rectifier Combo

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by metheniac, Feb 9, 2008.

  1. metheniac

    metheniac Supporting Member

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    I'm a 6v6 nut and was wondering which rectifier tube people prefer with htis power tube, a 5Y3 or 5AR4 or?? and do these 2 rec tubes require a significant adjustment to the bias and why. Does the 5AR4 run hotter?

    Be easy on me because I'm a dummy just trying to absorb as much as I can and not damage any equipment.
     
  2. burner

    burner Member

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    The 5Y3 will give you more 'sag' and the AR4 will give you a tighter sound.
     
  3. phsyconoodler

    phsyconoodler Member

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    A 5y3 has a greater voltage drop . 5AR4 has less internal resistance,has a slow warmup time and provides greater plate voltages.
    A relatively close formula is this:
    diodes = voltage x 1.4
    5y3 = voltage x 1.1
    5AR4 = voltage x 1.3

    This is approximate and varies a little from tube type,but is a good way to figure out what your plate voltage will end up at.A modern 5y3 is closer to a 5AR4 because it's not relly a true 5y3.
    By the way,the 5y3 will run hotter.
     
  4. Blue Strat

    Blue Strat Member

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  5. metheniac

    metheniac Supporting Member

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    This is great information to digest. Thanks for the responses so far.
     
  6. phsyconoodler

    phsyconoodler Member

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    A 5y3 is best left to 6v6 tubes and use a 5AR4 FOR 6L6 AND EL34.
    And as Blue Strat says,you can't just randomly mix and match rectifier tubes.There are parameters for each amp/tube combination and some rules can be bent a bit but you should be looking at tube data sheets and understand your amp's limitations before swapping rectifiers.
     

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